The present invention relates generally to a golf club, and more particularly to a golf club shaft made of composite material.
The conventional methods for making a composite material golf club shaft are xe2x80x9csheet-rolling methodxe2x80x9d and xe2x80x9cfilament winding methodxe2x80x9d. The sheet-rolling method includes the steps of cutting a fiber sheet preimpregnated with resin in accordance with predetermined various angles of fiber orientation into a plurality of sheets of various shapes and sizes. Stacking the fiber sheets together to form a fiber layer, and rolled it around an iron core. The advantage of the sheet-rolling method is the manufacturer can control the orientations of the fiber to make the shaft having a superior deflection capacity. But the disadvantage is the two edges of the fiber layer overlapped to form a xe2x80x9cspinexe2x80x9d on the shaft. The xe2x80x9cspinexe2x80x9d has more rigidity than the other section of the shaft to cause the shaft having an unhomogeneous mechanical property.
The filament winding method is winding a fiber tow around a core. Because of the winding procedure is controlled by a computer, so the shaft had a homogeneous mechanical property. But when winding, the orientations of the fibers are between 30 degrees to 45 degrees. It cannot provide an essential deflection capacity along the axle direction of the shaft.
Both of the methods described above cannot provide a perfect golf club shaft as people wishes.
The primary objective of the invention is to provide a golf club shaft, which has the advantages of the two methods described above.
According to the objective of the invention, a golf club shaft having a first segment and a second segment. The first segment is made by filament winding method, and the second is made by sheet-rolling method. The first segment and the second segment overlapped and fixed together to form the golf club shaft.